Wednesday

February 10, 2016
Total # Posts: 3,382

**physics**

Amy is 160 cm tall and stands 50 cm in front of a plane mirror. The image of Amy is:
*April 17, 2012*

**science**

Does adding boiled, deionized water to the titrating flask to wash the wall of the erlenmeyer flask and the buret tip increase, decrease, or have no effect on the Ksp value of the Ca(OH)2?
*April 17, 2012*

**Statistics**

Alonzo applied for a job to be an administrative assistant.He had to take a typing test. His words per minute were translated into a z-score. If the z-score was 0, should he be hired? There were 47 applicants, and typing speed is very important.
*April 8, 2012*

**Chemistry**

How did you find the concentration of [OH-]
*April 1, 2012*

**chemistry**

A dynamic equilibrium, Ag2CO3(s) <=> 2Ag+(ag) , CO3 2- (ag), what affect does the addition af HCl have on the system? Does it cause a shift?
*March 19, 2012*

**CHEMISTRY**

No problem! Thanks! :)
*March 18, 2012*

**CHEMISTRY**

Okay thanks sooooo much! I really really really appreciate your help! It's fine everyone makes mistakes! :)
*March 18, 2012*

**CHEMISTRY**

But Kf= 1.86 degrees C/m not 0.186? So shouldn't it be : dT = 1*1.86*14.46 =26.97 ---> -26.97
*March 18, 2012*

**CHEMISTRY**

What did you get for part b if you disagree with -26?
*March 18, 2012*

**CHEMISTRY**

oohhh so for part d I mixed up molarity and molality my bad...I get it now! So the answer I got in part a is supposed to be used in part d......Thanks! :)
*March 18, 2012*

**CHEMISTRY**

what did you get for part b then?
*March 18, 2012*

**CHEMISTRY**

sorry I typed it wrong....my answer for a) is 14.5 M
*March 18, 2012*

**CHEMISTRY**

for part c: 100g* 1L/920 g= .108695 L M=mols/L 0.87 mols of H2O/.108695 L =8.004 M Is this right? part d: pi= (8.004M) (0.08206) (-26.97+273)= 161.59 atm is this right?
*March 18, 2012*

**CHEMISTRY**

You mix 40.0 g of ethanol (C2H5OH, molecular weight = 46.1 g/mol) and 60.0 g of water (molecular weight = 18.0 g/mol) The resulting solution has a density of 920 g/L. a)Calculate the molarity of ethanol in this solution? Answer : 0.06 kg of H2O This is correct. b) At what ...
*March 18, 2012*

**Social studies **

Which of the following accurately describes a surplus? Consumer demand for a certain car is below the number of cars that are produced. The production costs for a certain car are below the sale price of that car. A car company tries to charge too high a price for a car and has...
*March 13, 2012*

**Math**

Thank you!
*March 8, 2012*

**Math**

Lily and Tina went to dinner. When the bill came, Lily discovered that she had only $6. Luckily, Tina had enough money to pay the rest or 3/5 of the bill. How much did Tina pay? How much was the total bill?
*March 8, 2012*

**Chem 100**

If the initial volume is 150mL and the final volume is 1L, what is the final pressure?
*March 1, 2012*

**English**

"Christina Nehring makes allusions to classical myths and 18th and 19th century writers in her essay "Fideltiy with a Wandering Eye". How do these allusions support her argument about women and sex? ALSO How effective are these allusions"
*February 29, 2012*

**math**

64 000 000 Square Millimeter Standard Form: 6.4 x 10 to the 6th power
*February 28, 2012*

**math grade 6**

Thanks fo the answer Cassie "18 chairs and six stools" Can you show me the working please. "a carpainter made 20 pieces of furniture comprising of 74 legs. stool of 3 legs and chairs of 4 legs. How many chairs and stools did he make"
*February 28, 2012*

**math grade 6**

a carpainter made 20 pieces of furniture comprising of 74 legs. stool of 3 legs and chairs of 4 legs. How many chairs and stools did he make.
*February 28, 2012*

**physic**

A rowboat crosses a river with a velocity of 3.42 mi/h at an angle 62.5° north of west relative to the water. The river is 0.610 mi wide and carries an eastward current of 1.25 mi/h. How far upstream is the boat when it reaches the opposite shore?
*February 26, 2012*

**Chemistry/Calorimetry**

You buy coffee (200.0 ml) served in a styrofoam cup. You are up late working in a chemistry lab, and want to drink the coffee right away, but at 95.0 degrees C, it is too hot to drink. You like the temperature of your coffee to be 79.0 ± 1.0 degrees C. You decide that ...
*February 23, 2012*

**early childhood**

evolutionary psychology and behavior genetics: watson
*February 23, 2012*

**Physics**

An astronaut is inside a rocket that is blasting off vertically from the launch pad. You want this rocket to reach the speed of sound (331 m/s) as quickly as possible, but you also do not want the astronaut to black out. Medical tests have shown that astronauts are in danger ...
*February 22, 2012*

**Chem**

Ohhh yeah i got it already. Thanks.
*February 18, 2012*

**Chem**

I got it! Thanks for the help...both of you :)
*February 18, 2012*

**Chem**

A solution is made by dissolving 0.584 mol of nonelectrolyte solute in 883 g of benzene. Calculate the freezing point and boiling point of the solution. Tf=? Tb=? I got Tf as 3.39 degrees Celsius I got Tb as 1.67 degrees Celsius It marked me wrong and said "You have given...
*February 18, 2012*

**Chemistry**

Thanks sooo much DrBob222! And I'm glad to help kylie :D
*February 18, 2012*

**Chemistry**

Sorry here are the data: Values at 20 degrees Celcius ethanol : density (g/mL)= 0.789/ vapor pressure (torr)= 43.9 water: density (g/mL) =0.998/ vapor pressure (torr)= 17.5 I' m still confused on what you are telling me to do :( Can u please clarify...
*February 18, 2012*

**math**

A company produces three types of color TVs: Models X, Y and Z. Each model X requires 2 hours of electronic work and 2 hours of assembly work. Each Y model requires 1 hour of electronic work and 3 hours of assembly work. Each model Z requires 3 hours of electronic work and 2 ...
*February 18, 2012*

**physics**

A baseball is thrown horizontally from a height of 12.00 m above the ground with a speed of 25.5 m/s. Where is the ball after 0.80 s have elapsed? The ball is a horizontal distance of m from the launch point.
*February 17, 2012*

**chemistry**

a bird is flying around the world at a rate of 88ft/sec,how many days will it take to complete this journey?
*February 14, 2012*

**General Physics II**

___A __/__\ B/____\C radius (each side of this equilateral triangle) 0.5 m Three point charges are located at the corners of an equilateral triangle as in the figure below. Find the magnitude and direction (counterclockwise from the +x-axis of the net electric force on the 0....
*February 11, 2012*

**Chemistry**

I am still having trouble as well...
*February 10, 2012*

**Chemistry**

Do I use the 293,000 j or 293 kj?
*February 10, 2012*

**Chemistry**

If the heat from burning 5.800 g of C6H6 is added to 5691 g of water at 21 °C, what is the final temperature of the water? 2C6H6(l) +15O2 (g)----> 12CO2(g)+6H2O(l) +6542
*February 10, 2012*

**Chemistry**

The density of liquid "A" is 1.80gm/ml, liquid "B" is 1.10 gm/ml and liquid "C" is 1.40 gm/ml. If theses liquids are immiscible in each other and a piece of solid with a specific gravity of 0.80 is placed in a container of all these liquids, what ...
*February 7, 2012*

**physics**

Two friends, Al and Jo, have a combined mass of 171 kg. At an ice skating rink they stand close together on skates, at rest and facing each other, with a compressed spring between them. The spring is kept from pushing them apart, because they are holding each other. When they ...
*January 25, 2012*

**Math**

A model rocket is shot straight up from the roof of a school. The height at any time t is approximated by the model h=-t^2+3t+28, where h is the height in meters and t is the time in seconds. When does the rocket hit the ground?
*January 24, 2012*

**physics**

A 0.579 kg basketball is dropped out of a window that is 6.22 m above the ground. The ball is caught by a person whose hands are 1.31 m above the ground. How much work is done on the ball by its weight?
*January 22, 2012*

**trig**

Please explain to me how to get this -- what quadrant tan theta < 0, sin theta < 0 is in.
*January 21, 2012*

**Trig**

what quadrant is this in and please explain... sin theta < 0, cos theta > 0
*January 21, 2012*

**trig**

5pi/7 what quadrant is it in???
*January 21, 2012*

**physics**

A 49.4 kg swimmer is standing on a stationary 214 kg floating raft. The swimmer then runs off the raft horizontally with a velocity of +3.60 m/s relative to the shore. Calculate the magnitude of the recoil velocity that the raft would have if there were no resistance due to ...
*January 19, 2012*

**physics**

A baseball (m = 149 g) approaches a bat horizontally at a speed of 39.8 m/s (89.0 mph) and is hit straight back at a speed of 45.8 m/s (102 mph). If the ball is in contact with the bat for a time of 1.27 ms, what is the average force exerted on the ball by the bat? Neglect the...
*January 19, 2012*

**languag arts**

In the sentence, "Sylvia looks good in her mermaid costume" why is good the correct word used as an adjective, as opposed to using well as an adverb. Isn't "good" describing how Sylvia looks?
*January 16, 2012*

**physics**

The three-toed sloth is the slowest moving land mammal. On the ground, the sloth moves at an average speed of 0.0330 m/s, considerably slower than the giant tortoise, which walks at 0.0800 m/s. After 10.2 minutes of walking, how much further would the tortoise have gone ...
*January 15, 2012*

**physics**

A woman on a bridge 77.4 m high sees a raft floating at a constant speed on the river below. She drops a stone from rest in an attempt to hit the raft. The stone is released when the raft has 7.07 m more to travel before passing under the bridge. The stone hits the water 4.18 ...
*January 15, 2012*

**physics**

An astronaut on a distant planet wants to determine its acceleration due to gravity. The astronaut throws a rock straight up with a velocity of 13.5 m/s and measures a time of 21.8 s before the rock returns to his hand. What is the acceleration due to gravity on this planet? (...
*January 15, 2012*

**physics**

Jordan tosses a ball upwards with an initial velocity of 14.0 m/s. What is the displacement in meters of the ball during the first 2.5 seconds after she threw it? (don't include units in the answer, use 10.0 m/s2 for g and use the upward direction as positive)
*January 11, 2012*

**physics**

Daniel tosses a ball upwards with an initial velocity of 10.0 m/s. In meters/second, what is the velocity of the ball 1.3 seconds after he threw it? (use 10.0 m/s2 for g and use the upward direction as positive)
*January 11, 2012*

**Physics**

Daniel tosses a ball upwards with an initial velocity of 10.0 m/s. In meters per second, what is the velocity of the ball 1.3 seconds after he threw it? (use 10.0 m/s2 for g and use the upward direction as positive)
*January 11, 2012*

**Physics**

A drag racer starts her car from rest and accelerates at 9.0 m/s2for the entire distance of 60.0 m. What is its speed at the end of the run? Answer in units of m/s.
*January 11, 2012*

**physics**

A drag racer starts her car from rest and accelerates at 9.0 m/s2for the entire distance of 105.0 m. What is its speed at the end of the run? Answer in units of m/s.
*January 11, 2012*

**solid geometry**

what are the dimensions of a gallon can of uniform square cross section whose height is twice the length of an edge of its base?
*January 10, 2012*

**statistics**

Records show that deaths occur at the rate of 0.1 per day among patients residing in a large nursing home. If someone dies today, what are the chances that a week or more will elapse before another death occurs? The answer is 0.50 and the problem is in the Poisson section but ...
*December 11, 2011*

**physics**

A merry-go-round in a playground has a mass of 200 kg and radius of 1.50 m. You apply a force F = 23 N tangentially to the edge of the merry-go-round for a time of 6.5 s. The moment of inertia of the merry-go-round is 1/2(mR2). What is the angular acceleration of the merry-go-...
*December 9, 2011*

**HELLLLP Math**

nm figured it out
*December 8, 2011*

**HELLLLP Math**

A steel tube, which is closed at both ends, is filled with air. The air in the tube is vibrating at a frequency of 200·Hz. Use 340·m/s for the speed of sound in air. If the 200·Hz vibration respresents the fundamental standing wave for the tube, how long ...
*December 8, 2011*

**math**

A woman is sitting in a boat at anchor on a lake. Her boat bobs up and down once every 2.0·s. She notices that when the front of her 3.0·m long boat is at one wave crest, a second crest is at the middle of her boat, and a third is at the end. What is the ...
*December 8, 2011*

**physics**

A steel tube, which is closed at both ends, is filled with air. The air in the tube is vibrating at a frequency of 200·Hz. Use 340·m/s for the speed of sound in air. (a) What is the wavelength of the sound waves in the tube? _____ m. (b) If the 200·Hz ...
*December 8, 2011*

**Pensacola State**

The solubility of NH3 in H20 is 518 g/L at a partial pressure of 760.0 torr. 1. Calculate the value of the Henry's Law constant for NH3. 2. calculate the solubility of NH3 in H2O at a partial pressure of 225.0 torr.
*December 6, 2011*

**statistics**

what happens to the width of our confidence interval for mu if we increase the sample size but keep the confidence level the same ? a. it increases b. it stays the same c. it decreases d. it depends on the sample mean and standard deviation
*December 6, 2011*

**statistics**

according to the energy information administration (officially energy statics from the US Government) the mean price for one gallon of unleaded regular gas in the US cities for the year 2007 was 2.80 A random sample of 30 pumps in georgia yielded and average price of 284 per ...
*December 6, 2011*

**statistics**

a recent study suggests that the mean maximum temperature for the month of december in nyc is different from 41 degrees F. provide the null and alternative hypotheses for this test.
*December 6, 2011*

**statistics**

we are interested in testing at level of significance alpha =10 whether the population mean is different than 15. a random sample of size 25 is taken with a mean of 13.9. assume standard deviation is 2 and normally distributed population. find the values for zcrit
*December 6, 2011*

**statistics**

Assume that body temperatures of healthy adults are normally distributed with a mean of 98.2 degrees F and a standard deviation of .62 degrees F. suppose we take a sample of eight healthy adults. what is the probability that their mean body temperature will be greater than 98.4
*December 6, 2011*

**statistics**

Assume that body temperatures of healthy adults are normally distributed with a mean of 98.2 degrees F and a standard deviation of .62 degrees F. suppose we take a sample of eight healthy adults. what is the probability that their mean body temperature will be greater than 98.4
*December 6, 2011*

**pre-algebra**

We need more info. What is the full problem?
*December 6, 2011*

**geometry**

(1)r y-axis °r x-axis (2)T 2,-3 °y=x (3)r y=-x °D 3 (4)R o °R o HELP!!
*December 4, 2011*

**geometry**

Which composition would produce an image triangle whose area is not equal to the area of the original triangle?
*December 4, 2011*

**math**

Suppose that fifteen observations are chosen at random from the pdf f_Y(y) = 3y^2, 0<=y<=1. Let X denote the number that lie in the interval (1/2, 1). Find E(X). E(X) is the expected value or average.
*November 29, 2011*

**finance**

I am thinking that the answer is c because if the company is operating above its breakeven point and the fixed costs are constant then the profits should increase by more than 15% since they aren't receiving any additional costs.
*November 27, 2011*

**finance**

If a company has fixed costs and is operating above the breakeven point, when sales increase by 15%, profits will: a. increase by less than 15% b. increase by 15% c. increase by more than 15% d. decrease by less than 15%
*November 27, 2011*

**math**

two integers have sum of 23 and a difference of 7. which of the following is also true about these integers? A they have a product of 161. B they have a qoutient 4. C they have a product of 120. D they have a qoutient of 2.
*November 23, 2011*

**american history**

Yo chill anonymous :(
*November 19, 2011*

**physics**

A .1kg mass is located on the line between a 5kg mass and a 10kg mass. It is 4m to the right of the 5kg mass and 6m go the left of the 10kg mass. What is the magnitude and direction of the net force on the .1kg mass?
*November 17, 2011*

**math**

an amount invested in an account that offers 5% interest which is compounded annually. how long will it take for this amount to double?
*November 17, 2011*

**physics**

a helicopter has a speed relative to the air of 76km/h northeast. The speed of the wind relative to the ground is 28km/h south. 2 hours after leaving the ground, what is the displacement of the helicopter relative to the ground?
*November 11, 2011*

**math**

a) 7.49 miles b) 0.12 miles per minute
*November 10, 2011*

**Biology**

How can you experimentally determine the total volume of blood in a human?
*November 6, 2011*

**Science**

Are you then suggesting that because humans are not predators, their eyes have a more constricted view than owls?
*November 6, 2011*

**Science**

Why are your ears at the side of your head and not in front where your eyes are?
*November 6, 2011*

**chemistry**

sample of argon gas collected at a pressure of 1.11 atm and a temperature of 28.0 oC is found to occupy a volume of 20.3 liters. How many moles of Ar gas are in the sample?
*November 5, 2011*

**Physics**

A rock thrown with an initial velocity of 35 m/s at an angle of 48° with respect to the horizontal has a range of 963 m on a certain planet. What is the acceleration of gravity on this planet?
*November 4, 2011*

**MATH**

Assume that the population of heights of male college students is approximately normally distributed with mean of 72.83 inches and standard deviation of 6.86 inches. A random sample of 93 heights is obtained. Show all work. (A) Find the mean and standard error of the x ...
*November 3, 2011*

**MATH...PLZ HELP**

The width of the Confidence Interval is inversely related to the Maximum Error of Estimate. T or F? Why or why not?
*November 3, 2011*

**MATH....**

Determine the level of the confidence given the confidence coefficient z(α/2) for the following situation: z(α/2) = 1.96
*November 3, 2011*

**MATH**

Given a binomial distribution with n = 21 and p = 0.76, would the normal distribution provide a reasonable approximation? Why or why not?
*November 2, 2011*

**Math**

pattern rule for 2,3, ___, 7, 11, 13, 17, ___
*November 2, 2011*

**physics**

thank you so much!!!
*November 2, 2011*

**physics**

thank you! From here how would I get this: Suppose the torque you found for the last part is being produced by a force applied at a point 0.15·m from the axis. If the direction of the force is perpendicular to a line from the axis to that point, what is the magnitude of...
*November 2, 2011*

**physics**

Consider a 8·kg rod with a length of 0.6·m and rotating about an axis passing through its center. (a) What is its rotational inertia? (B) Suppose the rod is rotating counterclockwise and speeding up with a rotational acceleration of 7·rad/s2. What is the ...
*November 2, 2011*

**math**

Consider a 8·kg rod with a length of 0.6·m and rotating about an axis passing through its center. (a) What is its rotational inertia?
*November 2, 2011*

**math**

Consider a 8·kg rod with a length of 0.6·m and rotating about an axis passing through its center. (a) What is its rotational inertia?
*November 2, 2011*

**Biology**

Can genetic mutations also occur within mitochondria and cause diseases? if yes, how common are these diseases?
*October 31, 2011*

**Chemistry**

Hydrogen sulfide is an impurity in natural gas that must be removed. One common removal method is called the Claus process, which relies on the reaction: 8 H2S(g) + 4 O2(g)--> S(l) + 8 H2O(g) Under optimal conditions the Claus process gives 98% yield of S8 from H2S. If you ...
*October 31, 2011*

**Chemistry**

Which of the following solutions is the most basic? (a) 0.6 M NH3, (b) 0.150 M KOH, (c) 0.100 M Ba(OH)2. Explain.
*October 31, 2011*